title: Application of complexation high-speed counter-current chromatography in the separation of 5-hydroxyisoflavone isomers from Belamcanda chinensis (L.) DC.
abstract: A novel separation technique of complexation high-speed counter-current chromatography (HSCCC) using copper ion as a complexation agent was first developed to isolate 5-hydroxyisoflavone isomers from Belamcanda chinensis (L.) DC. According to the partition coefficient and separation factor, the two-phase solvent system composed of light petroleum-ethyl acetate-methanol-water (3:5:3:5, v/v) and copper nitrate (0.10mol/L in the lower phase) was selected. 9.2mg isoirigenin (1), 46.4mg irigenin (2) and 1.2mg 5,7,4'-trihydroxy-6,3',5'-trimethoxyisoflavone (3) were simultaneously purified from 100mg crude extract by HSCCC with the purity of 95.06%, 96.98% and 93.69%, respectively. As evidenced by the results of UV-Vis spectroscopy, the stoichiometries of the copper ion with the three 5-hydroxyisoflavones were all 1:1 and their chelating power was 3>2>1. Those explained the complexation HSCCC behavior. It is the first report that includes the practical application of complexation HSCCC and explanation of its chromatographic behavior.
authors.affiliation: Department of Natural Medicinal Chemistry, China Pharmaceutical University, 24 Tong Jia Xiang, Nanjing 210009, Jiangsu, China.
authors.forename: Weina
authors.initials: W
authors.lastname: Liu
authors.forename: Jianguang
authors.initials: J
authors.lastname: Luo
authors.forename: Lingyi
authors.initials: L
authors.lastname: Kong
mesh_terms: D002614:Chelating Agents / Q000737:chemistry; D003300:Copper / Q000737:chemistry; D003377:Countercurrent Distribution / Q000379:methods*; D027621:Iridaceae / Q000737:chemistry*; D007529:Isoflavones / Q000737:chemistry / Q000302:isolation & purification*; D007536:Isomerism; D016014:Linear Models; D010936:Plant Extracts / Q000737:chemistry; D027343:Rhizome / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002614:Chelating Agents; D007529:Isoflavones; D010936:Plant Extracts; D003300:Copper